IJSRD - International Journal for Scientific Research & Development| Vol. 3, Issue 10, 2015 | ISSN (online): 2321-0613
Thermal and Structural Analysis using FEA on Pillar Vans Type Ventilated Disc Brake Rotor 1,2
Anurag Patel1 Ankur Malviya2 Christian College of Engineering and Technology Bhilai Chhattisgarh, India
Abstract— Safety aspect in automotive engineering has been considered as a number one priority in development of new vehicle. Each single system has been studied and developed in order to meet safety requirement. Instead of having good suspension systems, Air bags, good handling and safe cornering, there is one most critical system in the vehicle which is brake systems. Without brake system in the vehicle will put a passenger in unsafe position. Therefore, it is must for all vehicles to have proper brake system. For the purpose of safety and increased life cycle of the disc brakes this paper deals with the design modification of a disc break so as to produce better thermal and structural performance. Key words: Disc Brake, FEA, Suspension Systems I. INTRODUCTION The brakes are one of the most important aspects of a vehicle since it fulfills all the stopping functions and requirements. A brake is a device by means of which artificial frictional resistance is applied to moving machine member, in order to stop the motion of a machine. Braking is a process which converts the kinetic energy of the vehicle into mechanical energy which must be dissipated in the form of heat. During the braking phase, the frictional heat generated at the interface disc - pads can lead to high temperatures. This phenomenon is even more important that the tangential stress as well as the relative sliding speeds in contact is important. As trivial as brakes may appear to be, many issues surround their heating characteristics when it comes to their development, including material choice, contact region properties, development of hot spots, associated physical geometry, and thermo-elastic deformations. A. 1) 2) 3) 4) 5)
Component of Disc Brake: Calliper Brake pads Brake Pad Materials: Asbestos Non-Asbestos Organics Semi-Metallic Low Steel Carbon Piston and cylinder Disc brake rotor
B. Disc brake rotor: The disc brake rotor is the disc component against which the brake pads are applied. The ventilated type rotor consists of holes, slots and cooling fins to ensure good cooling. Many high performance brakes have holes drilled through them for a heat dissipation purpose which is known as cross-drilling. Slotted Discs are mostly preferred in racing cars, within which shallow channels are machined thus, helping in removing dust, gas and water. Some disc are both drilled and slotted. In the wet condition the slotted and drilled rotor have a positive effect.
Material of disc rotor: 1) Nickel Chrome Steel. 2) Aluminum Alloy. 3) Cast Iron. 4) Carbon Reinforced polymer. 5) Titanium Alloy. II. DISC BRAKE ROTOR FAILURE MODES The various types of disc brake failures are explained in the following sections. - Thermo-mechanical distortion - Cracking Problems in disc brake by applying brake, shoo pad is grip the disc of disc brake due to that stopping of their rotation and converting kinetic energy in to heat energy due to rapidly apply brake there is thermal expansion of disc. Due to thermal Expiation of disc brake jamming of disc in brake shoo. Static analysis is used to determine the displacements, stresses, strains and forces in structures or components due to the loads that do not include significant inertia and damping effects. Steady loading in response conditions are assumed. The kind of loading that can be applied in a static analysis include externally applied forces and pressures, steady state Inertia forces such as gravity or rotational velocity imposed (non zero) displacements, temperatures (for thermal strain).
Fig. 1: Model of Disc Brake Rotor III. MATERIAL PROPERTIES A. Cast Iron: Cast iron usually refers to grey cast iron, but identifies a large group of ferrous alloys, which solidify with a eutectic. Iron accounts for more than 95%, while the main alloying elements are carbon and silicon. The amount of carbon in cast iron is the range 2.1-4%, as ferrous alloys with less are denoted carbon steel by definition. Cast irons contain appreciable amounts of silicon, normally 1-3%, and consequently these alloys should be considered ternary FeC-Si alloys. Here graphite is present in the form of flakes. Disc brake discs are commonly manufactured out of a material called grey cast iron.
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Thermal and Structural Analysis using FEA on Pillar Vans Type Ventilated Disc Brake Rotor (IJSRD/Vol. 3/Issue 10/2015/190)
efforts such as those caused by time varying loads. A static analysis can, however include steady inertia loads (such as gravity and rotational velocity), and time varying loads that can be approximated as static equivalent wind and seismic loads commonly defined in many building codes).
Fig. 2: Material Properties of Cast Iron
C. Dimensions of disc brake: The dimensions of brake disc used for thermal and static structural analysis are shown in fig. Outer diameter = 262 mm Inner diameter = 60 mm Thickness = 24 mm Air gap = 8 mm No. of vans = 24
Fig. 5: Dimension of the Disc Brake Rotor
Fig. 3: Material Properties of Stainless Steel In the finite element analysis, the basic concept is to analyze the structure, which is an assemblage of discrete pieces called elements, which are connected together at a finite number of points called Nodes. A network of these elements is known as Mesh. As shown in fig.
D. Input Parameters: The input parameters are as follows: 1) Mass of the vehicle = 2500 kg 2) Initial velocity (u) = 27.78 m/s (100 kmph) 3) Vehicle speed at the end of the braking application (v) = 0 m/s 4) Brake rotor diameter = 0.262 m 5) Axle weight distribution 30% on each side (γ) = 0.3 6) Percentage of kinetic energy that disc absorbs (90%) k = 0.9 7) Acceleration due to gravity g = 9.81m/s2 8) Coefficient of friction for dry pavement μ = 0.7 9) Diameter of the drill holes = 8 mm 10) No. of holes = 24 on each face 1) Case 1:
Fig. 4: Meshed Model IV. THERMAL ANALYSIS A. Heat Convection: Energy is carried away from the surface by convection that is motion of the air removes the heated air near the surface and replaces it with cooler air. The finding by Sheridan (1988) suggested that 90% of the heat generated during braking is transferred by convection to the ambient air. Qconv = hAs (Ts – T∞) (1)
Fig. 6: Ventilated Type Drilled Disc Rotor with Face Groove
B. Static and structural analysis: A static analysis calculates the effects of steady loading condition on a structure, while ignoring inertia and damping
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Thermal and Structural Analysis using FEA on Pillar Vans Type Ventilated Disc Brake Rotor (IJSRD/Vol. 3/Issue 10/2015/190)
Fig. 7: Temperature Contours for Ventilated Type Drilled Disc Rotor of Cast Iron
Fig. 8: Total Deflection of Ventilated Type Drilled Disc Rotor of Cast Iron
Fig. 11: Total Deflection of Ventilated Type Drilled Disc Rotor of Stainless Steel
Fig. 12: Von Misses Stress on Ventilated Disc Rotor of Stainless Steel 2) Case 2: Now for the different model which is dimensionally different from previous model, same condition is applied. Flange width = 9 mm each face Air gap = 6 mm Vent = pillared type as shown in fig 13.
Fig. 9: Von Misses Stress on Ventilated Disc Rotor of Cast Iron
Fig. 13: Ventilated Type Disc Rotor with Pillared Vans
Fig. 10: Temperature Contours for Ventilated Type Drilled Disc Rotor of Stainless Steel
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Thermal and Structural Analysis using FEA on Pillar Vans Type Ventilated Disc Brake Rotor (IJSRD/Vol. 3/Issue 10/2015/190)
Fig. 14: Temperature Contours Pillared Type Ventilated Disc Rotor of Cast Iron
Fig. 15: Total Deflection of Pillared Type Ventilated Disc Rotor of Cast Iron
Fig. 18: Total Deflection of Pillared Type Ventilated Disc Rotor of Stainless Steel
Fig. 19: Von Misses Stress on Pillared Type Ventilated Disc Rotor of Stainless Steel V. CONCLUSION By the transient thermal and static structural analysis of Disc brakes it is observed that from deformation point of view the stainless steel can provide better brake performance than others whereas from stress point of view cast iron provides better performance. The present study can provide a useful design tool and improve the brake performance of Disc brake system. REFERENCE
Fig. 16: Von Misses Stress on Pillared Type Ventilated Disc Rotor of Cast Iron
[1] “Report of Analysis of a Ventilated Disc Brake Rotor Using CFD to improve its thermal performance Analysis of a Ventilated Disc Brake Rotor Using CFD to improve its,” no. SEPTEMBER, 2015. [2] S. P. Rec, “Strength Analysis of a Ventilated Brake Disc- Hub Assembly for a Multiutility Vehicle STRENGTH ANALYSIS OF A VENTILATED BRAKE DISC-HUB ASSEMBLY FOR A MULTIUTILITY VEHICLE.,” no. MAY, pp. 0–5, 2015. [3] B. Inbasekar, “Design and Optimization of Ventilated Disc Brake for Heat Dissipation,” vol. 2, no. 3, pp. 692–694, 2015. [4] B. Ali and N. M. Ghazaly, “Thermal Modeling of Disc Brake Rotor in Frictional Contact,” J. Multiscale Model., vol. 05, no. 03, p. 1350013, 2013.
Fig. 17: Total Deflection of Pillared Type Ventilated Disc Rotor of Stainless Steel
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Thermal and Structural Analysis using FEA on Pillar Vans Type Ventilated Disc Brake Rotor (IJSRD/Vol. 3/Issue 10/2015/190)
[5] K. Shahril, M. Ridzuan and M. Sabri '' Thermal Effects of Disc Brake Rotor Design for Automotive Brake Application'' 2013 [6] P. Sandeep and P. P. Valji, “Design Modification of Disc Brake and Performance Analysis of it by varying the Patterns of Hole,” vol. 2, no. 09, pp. 393–395, 2014. [7] Deepak Biradar, M.R.Chopde, Dr. S.B.Barve ''experimental analysis and investigation for thermal behavior of Ventilated disc brake rotor'' a review 07 2014 [8] Viraj Parab, Kunal Naik, Prof A. D. Dhale, '' Structural and Thermal Analysis of Brake Disc'' ijedr 2014 13981403 [9] M. Bouchetara, A. Belhocine, M. Nouby, D. C. Barton, and A. Bakar, “Thermal analysis of ventilated and full disc brake rotors with frictional heat generation,” no. JULY, 2014. [10] M. H. Pendkar, P. S. P. Gaikwad, and V. N. Kongari, “THERMAL ANALYSIS OF 150 cc PULSAR DISC BRAKE,” vol. 3, no. 6, pp. 63–67, 2014. [11] V. V. Shinde, C. D. Sagar, and P. Baskar, “Thermal and Structural Analysis of Disc Brake for Different Cut Patterns,” vol. 11, no. 2, pp. 84–87, 2014. [12] I. Gupta, G. Saxena, and V. Modi, “Thermal Analysis of Rotor Disc of Disc Brake of Baja Sae 2013 Car Through Finite Element Analysis,” no. March, pp. 324–329, 2014. [13] N. Balasubramanyam, “Design and Analysis of Disc Brake Rotor for a Two Wheeler,” vol. 1, no. 1, pp. 7– 12, 2014. [14] [14] A. K. Rai, P. R. Reddy, and A. Jabbar, “DESIGN AND STRUCTURAL ANALYSIS OF DISC BRAKE IN AUTOMOBILES Classification of Brakes (Based on Transformation of Energy),” vol. 4, no. 1, pp. 95–112, 2014. [15] S. R. Abhang and D. P. Bhaskar, “Design and Analysis of Disc Brake,” Int. J. Eng. Trends Technol., vol. 8, no. 4, pp. 165–167, 2014. [16] Mahmood Hasan Dakhil, Dr. A. K. Rai, Dr. P. Ravinder Reedy & Ahmed Abdulhussein Jabbar '' Structural Design and Analysis of Disc brake in Automobiles'' jan 2014 [17] I. Journal, “Structural and Thermal Analysis of Rotor Disc of Disc Brake,” vol. 2, no. 12, pp. 7741–7749, 2013. [18] V. C. Reddy, M. G. Reddy, and G. H. Gowd, “Modeling and Analysis of FSAE Car Disc Brake Using FEM,” vol. 3, no. 9, pp. 383–389, 2013. [19] A. Belhocine and M. Bouchetara, “Thermo-mechanical Analysis of a Disc Braking System,” pp. 302–309, 2013.
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